A 4-year-old girl is evaluated for a dark growth on her ankle. Her parents first noted the lesion approximately 4 months earlier and report that it is slowly enlarging. The child is of average height, weight, and development. Family history is negative for skin cancer and genodermatoses. Physical examination reveals a 1.0 cm hyperpigmented slightly raised lesion of her left ankle with a well-defined border. Dermoscopic evaluation reveals a starburst pigmentary pattern. No similar lesions are noted elsewhere on the child’s body.
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Spitz nevus, also known as spindle and epithelioid cell nevus, is an uncommonly encountered melanocytic neoplasm that most often occurs in children. These melanocytic proliferations were first recognized by the American pathologist Sophie Spitz. She referred to growths as “benign juvenile melanomas” because of the histologic similarity to melanoma but with a benign clinical course.1 The classic presentation is that of a well-circumscribed, dome-shaped pink papule or plaque on the face or lower extremities. Pigmented lesions occur in approximately 10% of cases and these clinically resemble a lentigo or acquired junctional melanocytic nevus with coloration ranging from light brown to black.2
On dermoscopic examination, pigmented lesions may reveal a ‘starburst’ pattern consisting of a central area of homogeneous black-blue pigmentation accompanied by symmetrically distributed peripheral streaks or pseudopods.3 Histology reveals spindled and/or epithelioid melanocytes with large nuclei and abundant cytoplasm. Kamino bodies are characteristic of the Spitz nevus and appear as pink amorphic periodic acid-Schiff (PAS)-positive globules within the epidermis.4
Many clinicians believe that Spitz nevi displaying clinical and dermoscopic benign features may be managed conservatively.3 However, lesions that display worrisome histologic features such as asymmetry, diffuse pagetoid spread, and cytologic atypia, have malignant potential and warrant more aggressive therapy.5 Histopathologic differentiation from melanoma may be difficult and a small percentage of these lesions may represent evolving Spitzoid melanoma with metastatic potential. One of the 13 children described in Spitz’s original study died of malignant melanoma.6
Stephen Schleicher, MD, is director of the DermDox Dermatology Centers, associate professor of medicine at Geisinger Commonwealth Medical College, and clinical instructor of dermatology at Arcadia University and Kings College.
1. Spitz S. Melanomas of childhood. Am J Pathol. 1948;24:591–609.
2. Luo S, Sepehr A, Tsao H. Spitz nevi and other Spitzoid lesions part I. Background and diagnoses. J Am Acad Dermatol. 2011;65(6):1073-1084. doi:10.1016/j.jaad.2011.04.040
3. Brunetti B, Briatico G, Scharf C, et al. Stardust pattern as evolution of pigmented spitz nevi during childhood. Dermatol Pract Concept. 2023;13(1):e2023041. doi:10.5826/dpc.1301a41
4. Venkatesh D, Smitha T. Kamino bodies. J Oral Maxillofac Pathol. 2019;23(1):17-18. doi:10.4103/jomfp.JOMFP_84_19
5. Dal Pozzo CA, Cappellesso R. The morpho-molecular landscape of Spitz neoplasms. Int J Mol Sci. 2022;23(8):4211. doi:10.3390/ijms23084211
6. Shah KA. Spitz nevus. Dermatology Advisor. March 13, 2019. Accessed July 12, 2023, https://www.dermatologyadvisor.com/home/decision-support-in-medicine/dermatology/spitz-nevus/